The present invention relates to a friction roller conveyor, and more particularly to a conveyor that includes friction rollers within a housing and a housing cover with openings through which the friction rollers partially extend and which rollers are secured against axial shifting and are driven.
German Pat. No. 3 017 942 discloses a friction roller conveyor of the above mentioned type in which slide rings are arranged on a drive shaft which are nonrotatably connected with the drive shaft. A ring surrounding the slide ring is driven by friction. In this case, the ring is driven to the slide ring and this again to the drive shaft. Such an arrangement is not only expensive but is subject to severe wear and in addition is very difficult to repair.
German Pat. No. 3 439 966 discloses a conveying device for piece goods and the like. Rolling elements, directly support the piece goods. The rolling elements are arranged below a plate or a plate-like segment on carrying, rolling drive equipment and such rolling elements run in openings in the plate. The rolling element project above the top surface of the plate and are arranged in straight rows transversely to the conveying direction. The rolling drive apparatus consists of cylindrical shafts each supported in bearings in the center under the row of rolling element as well as parallel to these rows. Such conveying devices for piece goods generally disclosed as ball conveyors have the disadvantage of high Hertzian pressure against the goods to be transported and this equipment is very expensive since it must be assured that the drive shafts are firmly connected via bearings with the plates carrying the guides for the balls. Otherwise a sliding away of the balls below the plates is possible. As a result of the high Hertzian pressure, severe wear is produced not only against the goods to be conveyed but also against the bearings for the drive shaft and the drive shaft itself. For repairs, the entire conveyor equipment must be disassembled which leads to long down times of such conveyor equipment.